


A mission for the Margravate

by Sawcha



Category: Fire Emblem: Fuukasetsugetsu | Fire Emblem: Three Houses
Genre: AU, Childhood, Family, Fatherhood, Gen, Mercenaries, Non-Binary Byleth, Young Sylvain Jose Gautier, blue lions - Freeform, young Byleth
Language: English
Status: Completed
Published: 2021-03-03
Updated: 2021-03-03
Packaged: 2021-03-16 08:34:27
Rating: General Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 3,194
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/29822238
Author URL: https://archiveofourown.org/users/Sawcha/pseuds/Sawcha
Summary: Jeralt's mercenaries have a mission at the Margravate's castle in the Holy Kingdom of Faerghus. During the meeting with the landlord, Byleth, Jeralt's child, meets Sylvain, the Margravate's son. But what will happen when they discover the mission concerns Sylvain himself ?AU where Byleth meets Sylvain when they were children
Kudos: 4





	A mission for the Margravate

**Author's Note:**

> If I misgendered Byleth, please let me know   
> Right before posting I realized Sylvain's last name was Gautier and not Gauthier so I tried to change it but maybe there's some times where I forgot to do so

« Hey kiddo »

Byleth was awoken by their father's voice. Half-asleep, the child took a while to recognize where Jeralt's mercenaries were. All that they knew was that the temperature was really cold. Every unit was wearing gloves with fur to warm themselves a little bit. Jeralt was holding his child in his arms. He knew his kid well enough to know that they would be tired after so much walking and was carrying them without complains. Byleth looked at their father, a little bit lost.

« You're okay ? »

He asked, seeing how little their eyes were. The blue-haired child quietly nodded, as they usually do. They were not really talkative but Jeralt was used to it. Some of his troups didn't even heard their voice at least once, but they didn't mind. Byleth was the child of their boss and they were a pretty good unit too. Their quiet nature make them almost invisible, which was perfect if they had to hunt in the forest or to track ennemies. And they were good in battle too ! Who wouldn't be with such a good trainer as their father ?  
But even thought the child nodded, they were still feel lost. Where were they ? Jeralt noticed this attitude quickly.

« We were called by the margravate Gautier. We just arrived in his lands, by the way. »

Byleth remembered. They received a letter from the margravate, who needed mercenaries. The job was well-paid and most of the troups was enthusiastic about it : it was a bigger payment that what they usually had, after all... The other part of the troups was more septic and didn't really enjoy working for nobles that think they're superior to everyone. Moreover, nobles like that were frequent in the Holy Kingdom of Faerghus, were their mission was ! Crests were their obsession and they often go too far for them. The only ones who didn't take position were Jeralt and Byleth. Jeralt because he wanted to know more about what their mission was exactly. Byleth because it was their first time in the Kingdom.  
Their eyes got bigger when they looked at the snow. Byleth wasn't the kind of child who shows their emotions so it was kind of rare to see how fascinated they were by the white panorama facing them.

« It's your first time seeing snow, right ? It's nice, but quite cold. »

Jeralt put them back on the floor. Byleth walked on it, fascinated by the noises made by their foot. They took some snow in their hands, sculpting it into a not really round-shaped ball.

« We can play in it if you want to. But first we have to go to the margravate. Okay ? »

Byleth quietly nodded and followed their father into the halls of margravate Gautier's propriety. They were still discovering new things : Jeralt's mercernaries rarely worked into castles before. They worked mostly for small villages that needed help with creatures. But one thing was sure : Byleth didn't feel confortable in it. Sure, it was less noisy that when the villages were throwing feasts to thank them, but something in it was oppressive for the child. They took their father's hand and walked next to him. Even thought the place was more quiet when they arrived in front of the margravate's throne, Byleth didn't feel better. Was it some effect nobles do on the ones they receive ?

« Ah, I suppose you are Jeralt Eisner. »

Margravate Gautier said. Byleth looked at him. He was a gingerhead tall man, impressively well-dressed, in noble clothing and rings with stones on his fingers. He was holding regalias from the Gauthier house, especially a gigantic and terrifying spear. It was white as a bone and a red gemstone was taking place in it. But the most important was the young child, a gingerhead kid, who was playing with wooden toys on the floor.

« Sylvain, how many times have I told you to stand straight when we have visitors ?! »

Sylvain looked bored. He obeyed his father's orders, but it wasn't making him less bored. He hated when his father had visitors. He always had to be here to welcome them and most of the time, they weren't here to play with him but for diplomatics affairs he doesn't understand a word. But when he saw that this time there was a child his age within the guests, he smiled.

« Father, can I play with them ?  
\- Not now, we have important things to discuss.  
\- But Miklan always does what he wants... »

Sylvain was taking a risk, talking about Miklan like that. Just talking about Miklan in general. His big brother was kind of the unwanted child and the relationship between the father and the eldest son was broken. Sylvain was way too young to understand any of this. He was way too young to understand why his father was so angry everytime Sylvain was discussing his orders and talking about how his brother's life was so much better compared to his. But this time, margravate Gauthier remainded more calm.

« … Fine. You can go. »

With a loud joyful noise, the child ran to Byleth. They were still scared and confused by the atmosphere in here.

« My name is Sylvain ! Who are you ? You look cool ! Is that a real dagger ? So awesome ! »

Usually kids think Byleth is weird, so they don't really have a lot of friends their age. So when Sylvain started asking all this things, they didn't know what to say.

« How long will you stay here ? Maybe you'll meet my friends ! There's the prince Dimitri, Felix, his big brother Glenn and Ingrid ! We can make snowmen together !  
\- Snow... Men ? »

Byleth said. Their voice was so quiet that Sylvain was the only one to hear it. It was such a remarkable contrast with the gingerhead one, who was so loud !

« Yeah ! Wanna see the ones I did ? »

He didn't let any time for them to think about it that he was taking them to the garden. Before leaving Byleth heard their father's voice, telling them to be careful. Margravate Gauthier sighed after their leaving.

« Ah, kids... »

He looked pissed, but quickly changed his attitude when the children were gone. He looked more serious and polite, but his attitude seemed fake for Jeralt.

« I hope you had a safe trip. The Kingdom can be dangerous at this time of the year if you're not used to snowstorms...   
\- Is that why you called us ? »

This would have been unusual. Faërghus was used to this kind of weather, so hiring mercenaries just to handle snow looked a little bit strange.

« Oh, not at all. I asked you to come here because someone here needs protection. Their life is threatened.  
\- Did something happened to them ? We need to know every detail.  
\- It's... It's my son, Sylvain. »

Even thought Jeralt knew their child was good enough to defend themselves and other people, the father couldn't help himself to be worried about Byleth. Was it a good idea to leave them alone ? They weren't exactly all alone, since there was maids and servants in house Gauthier. Jeralt realized he needed to stay calm. He had to know more about the mission. The more he knew, the more he could help the two kids.

« You see, Sylvain is the hope of House Gauthier. He's the only one among my sons to have a crest and for the honor of this house, I can't allow to let anything happen to him. If I lose him, it will be the end of our family. »

Everyone stayed silent, but most of the mercenaries in here was filled with hate towards the margravate. This wasn't a way to raise a child ! A child is a human being, not someone you put all your expectations on. Jeralt would really like to give him a class or two on how to raise children, but margravate Gauthier was they employer. They couldn't complain, no matter how much they wanted to. They could only stay silent, but they didn't think less.

« Do you know who's after your son's life ?  
\- Sadly, I do. And it's no other than my first-born, Miklan. »

***

« Look ! It's a snowman ! »

Sylvain said when they arrived near some snowmen he built recently. Some had wooden arms, others had little rocks as faces... Byleth was enchanted. They didn't say much, but the face they made said a lot.

« They're cool, right ! I made them myself ! Here's Mister Pointy Teeths and next to him, it's Miss Lovely Face ! »

Those names were weird, but as usual Byleth didn't say anything. They were silently listening.

« You should try talking to them !  
\- Me ? They slowly said.  
\- Yeah ! Here, I'll show you. »

He got close to Miss Lovely Face and started to talk.

« Good evening, my Lady. You're really beautiful, today. Your face isn't the only lovely thing you have. You really take care of your hair, too ! It suits your eyes. »

Byleth wasn't used to hear a lot of nobles, but this really looked like high society ways of talking for him. This was impressive and really different from how he was talking before ! The snowwoman wasn't really beautiful to be honest. Her hair, made of dead leaves, was blown away even by the smallest winds. But it had some kind of charm, Byleth had to admit.

« Doing court to inanimate things again ? »

When they heard this voice coming from behind them, they suddenly turned around. It was Miklan, Sylvain's brother. The youngest looked annoyed to see him. He had just broken some fun they were having, after all.

« I'm training. When I'll get older, I'll have to do court to real women in order to keep house Gauthier alive.  
\- What kind of women would like someone who flirts with Ingrid Galatea's grandmother ? Miklan said to tease him.  
\- I-It was an accident ! »

Sylvain blushed, flustered. He wanted to look cool to their new friend, who was awesome to him. Mercenaries were awesome for the young Sylvain, after all.

« At least I'll be the future margravate and not you.  
\- You really want to be the best margravate, right ? Well, I can tell you how to be so. »

Sylvain looked interested but Byleth was more septic.

« You see the well in the forest ? You have to spend a night in it.  
\- W-What ?! No ! »

Sylvain looked scared.

« Why not ?  
\- You know why ! There's a monster in it ! A monster no one can defeat ! If I go there, I'm gonna get myself killed !  
\- But if you go there and stay in it, you'll show everyone how brave you are. Doesn't that sound perfect ? »

Sylvain didn't know what to say. This looked like a good opportunity to prove himself... But Byleth was still septic.

« Why are you helping him ? You hate him, right ? »

They said, with such a low voice Miklan asked them to repeat multiple times.

« I just want to help. That's all. He's my brother. I'll never be the margravate, so I'm helping him to be a good one. Stay out of it.  
\- Hey ! Don't talk like that to my friend !  
\- … Fine. They can come. We need witnesses, after all. »

They started walking throught the forest. It was getting cold. Sylvain was shaking, but not only because of the cold. He was getting scared. Being all alone, with the monster... It was terrifying. But he had to do it. He had to be brave. This was the only way for him to be taken seriously by everyone in Gauthier lands. And not only his father's lands. If he succeeds, he'll have such a good story to tell his friends ! They would be so proud of him.  
So when he saw the well, he was feeling more brave. He leaned on it, looking at the bottom.

« It's deep... »

Sylvain whispers. Miklan put a supportive hand on his back.

« Yeah, but you can do it.  
\- Can my friend come ?  
\- Sure. Hey kiddo. Come here. »

Byleth came closer, still septic. Sylvain looked at the well again.

« Miklan, I don't know. We should ask father first.  
\- It'll be okay. You said you'll do it, right ?  
\- I... »

But before Sylvain was able to say anything, Byleth felt Miklan's other hand on their back. Before they had the time to say anything, Miklan pushed them both in the well. The oldest's arms were too strong for Byleth to fight back. They found themselves both in the well. It was dark.

« M-Miklan !! »

Sylvain called. He couldn't hear them. But it was most likely for him to fake not hearing them. Sylvain only heard his brother's footsteps going far from the well. They were trapped !

« I-I'm... »

Sylvain shaked. He was terrified and nothing could calm him. Byleth was more rational, even if the fall hurt them on the knee.

« W-Wait ! You're bleeding ! »

Thanks to daylight, they could see a little bit. Sylvain saw that Byleth hurt themselves during the fall but they didn't seem to be really hurt. Indeed they took some of the fabric of their shirt and wrapped the injury in it.

« You're okay ? »

They asked. In this cold well, where everything was silent, they could hear Byleth's voice really clearly.

« Do you think we'll get out of here ? »

There was no rope to help them climb back. And even if there was, it would have been too dangerous to take it knowing Byleth's health. They could always scream and calm for help, but nobody would come. How could they hear them in a well lost in the middle of the woods ?   
But staying here wasn't the most terrifying. The most terrifying came when they heard a noise in the well. What was it ? Immediately, without asking any kind of questions, Byleth drew their dagger and took place in front of Sylvain, who was unarmed. He was scared and he was right to be so. The famous creature everyone was talking about was here. And it was horrible. It was a gigantic eyeless snake. Its smell was awful and on its scales there was little mouths where tongues were coming from. One of them caught Sylvain's arm but right before the young boy could say anything, Byleth cut the tongue in half. The creature screamed and focused on the blue-haired kid. Sylvain closed his eyes, too scared to move. All he could hear was Byleth screaming. It looked so off, knowing how silent they were until now. When he opened them again, he saw his new friend covered in blood. Was they... Dead ? But when he looked at it closer, he realized Byleth had just put their dagger in the creature's head and now, they were panting, covered in some terrifying creature's blood. The injury from before seemed insignificant when you looked at them, fearless, who had just killed a monster with only a small dagger.

« Wow... »

Was the only thing he managed to say. Byleth looked emotionless, like they were doing this everyday.

« You're okay ? You're... You're so strong ! You defeated it yourself ! »

He said, more and more speechless. When he saw Byleth's leg was shaking, he got closer to help them stand on their feets.

« We have to get out of here... But how ? »

He looked around himself, especially at the sky upon them. It was getting darker and the night was falling. So they really had to spend the night here... At least nothing was threatening their lives this time, but it wasn't less scary...  
But when he saw torches near the well, he started screaming. Seeing those torches, he thought someone was looking for them and he felt like it was the right thing to do to tell they were here.

« Kiddo ? »

He didn't recognized the voice until Byleth started screaming too.

« Father ! »

Someone they could trust ! A rope was thrown at them and they managed to get out of it. Once outside, the two children realized who saved them : their fathers. Next to them, two mercenaries were holding Miklan. Did they arrested him ?

« Are you hurt ? Jeralt asked when he saw his child.  
\- It's not my blood. »

Byleth simply said. They went in their father's arms, asking for a hug. They didn't looked like it, but Jeralt could guess it was a scary experience to live for them.

« It's over kiddo, you're safe now.  
\- Sir, your child is so cool ! They hurt their knee but they killed the creature in the well with their dagger ! »

Sylvain said. When he saw everyone confused faces, he told them the whole story. Margravate Gautier and his soldiers were shocked : what was this child made of to be able to defeat a gigantic creature almost with nothing ?

« What were you doing in here ? Margravate Gauthier asked.  
\- He pushed us. »

Byleth said, almost in an emotionless voice, as if they used all their feelings in the battle. They looked at Miklan, who was entirely denying. But Sylvain's version didn't help the eldest son : now everyone knew Miklan tried to kill both of them. Margravate Gauthier became silent but the expression on his face showed how much he was disappointed. He looked at one of his guards.

« Lead Mister Eisner and the children to the baths. »

He turned at his eldest son and the way he looked at him actually terrified Miklan.

« I'll deal with you later. »

Meanwhile, the two children were following Byleth's father. The blue-haired kid was still holding their dad's hand.

« Byleth ? »

Sylvain called. The child looked at him.

« When I grow up, I wanna be like you and protect everyone ! »

He said, in an admirative voice.

***

« Guys !! Have you heard the news ?! There's a new professor at the academy and they're gonna be our teacher ! »

With an energetic voice, Annette told everyone the news.

« Do you know who it is ? Ashe asked.  
\- I heard they save our Highness' life, Mercedes added.  
\- Then they have all my gratitude, Dedue simply said.  
\- I hope she's a cute girl, Sylvain said.  
\- I hope they're a good fighter, Felix added.  
\- Sylvain, Felix, it's our professor ! Please calm down a little bit ! Ingrid said with a sigh.  
\- They're coming ! »

At Annette's words, everyone stood still. Their house leader was leading their new professor in the classroom.

« And here's the Blue Lions. We hope to learn more with you at our side. But ! Don't put yourself too much pressure... »

Dimitri let them enter in the classroom. Ingrid looked at Sylvain during a short time, afraid he would try to seduce them. But he wasn't trying to seduce anyone, like he usually do. He was silent, almost in shock.

« No, it can't be... »

He said to himself. This dark-blue hair, this emotionless but fierce expression, this dagger on their hip... There had no doubt to have. It was definitely Byleth, the mercenary who saved his life years before.

« Do... Do you remember me ? »

He asked when he got closer to them.

« I-I'm Sylvain Jose Gautier. You saved my life years ago. »

Even if Byleth looked emotionless, something in their expression changed. They seemed to have recognized him.

« How is your knee now ? »

The other Blue Lions were confused. Felix and Ingrid were the most lost. Was it a way to seduce their teacher ? It didn't look like it.

« It's all better. Thank you. »

They said with a smile.

**Author's Note:**

> It's been a while since the last time I wrote something in english ! To be honest it was really hard for this one, so I think I'll post a french version of it !  
> I thought of this AU when I saw a fan-art of young Byleth rescuing young Dimitri (can't find it anymore tho). That's why I asked myself "what will happen if Byleth meets one of the students before being a teacher at Garreg Mach's monastery ?". The relationship between Sylvain and Miklan is something I already wrote about in a previous one-shot, but I think there's still something to do with them.   
> I hope you'll like it ! Next time I might write in french again but I don't know yet !


End file.
